69107159370domain: NAppears in sequencesa(n) = 1^n + 2^n + 3^n + 4^n.at n=18A0015511 + 4^n + 9^n + 16^n.at n=8A091775a(n) = Sum_{k=0..floor(n/2)} k^(2*n).at n=9A352983